【摘要】 压痕和刻划实验是测量材料弹性、塑性和断裂行为的最简单方法,磷酸二氢钾(简称KDP)作为优质的非线性光学材料,常用作光学频率转换器件和电光开关元件,一般采用单点金刚石车削的方法加工此类零件.为了深入了解KDP晶体单点金刚石切削加工表层力学性能的变化规律,本文对KDP晶体单点金刚石切削加工表层力学性能指标如硬度Hv、断裂韧性KC和残余应力σr方面的有关问题进行深入研究,并通过对KDP晶体(001)面不同晶向上的硬度检测,系统分析了KDP晶体加工表面晶向对材料硬度、断裂韧性和残余应力的影响,研究结果表明:KDP晶体的同一晶面的不同晶向硬度和断裂韧性具有强烈的各向异性.更多还原

【Abstract】 Indentation and single-point scratch tests are probably the simplest methods to measure the elastic,plastic and fracture behavior of brittle materials.Potassium Dihydrogen Phosphate(KDP) is a non-linear optical material used for laser frequency conversion and electrooptic modulators,it is typically machined by single point diamond turning.In this paper,in order to in-depth understand the near-surface mechanical properties of Potassium Dihydrogen Phosphate(KDP) crystals in diamond turning.The near-surface mechanical properties have been investigated include the plastic property,hardness H;the fracture property,fracture toughness Kc and residual stressσr.Hardness of KDP crystals on(001) plane are examined under different loads,the influence of crystallographic orientation on hardness,fracture toughness and residual stress are also analyzed systematically.The results show that the hardness and fracture toughness have strongly anisotropy in different crystallographic orientations of the same crystal plane.更多还原